Continuously or infinitely variable transmission free of over-running clutches

ABSTRACT

An oscillating ratchet style continuously or infinitely variable transmission is disclosed herein, that is, one which, in its operation, relies on a plurality of different successive intermediate rotations that vary in speed and direction in accordance with their own respective oscillatory waveform, each waveform being out of phase with one another in a predetermined way. These intermediate rotations are used to convert the rotational input to a plurality of uni-directional output rotations, without the said of any over-running clutches. These later outputs vary in speed in accordance with their own respective waveforms and are used to produce a modified rotational output.

This is a continuation of application Ser. No. 660,292 filed Feb. 22,1991, now U.S. Pat. No. 5,226,859.

The present invention relates generally to racheting style infinitely orcontinuously variable transmissions (IVTs) generally and moreparticularly to an IVT including a specifically designed high speedswitching assembly instead of over-running clutches. An IVT of thegeneral type to which the present invention is directed is disclosed inU.S. Pat. No. 4,983,151 to Paul B. Pires on Jan. 8, 1991 andincorporated herein by reference.

A transmission is a device which accepts a rotational power input, froman engine and by way of changing ratios (mechanical advantage), changestorque and speed components to more closely match the demands of theoutput usage need.

There are three basic types of mechanical transmissions which employ"hard gearing" to conduct power from the input to the output and tochange ratios. They are set forth immediately below and a briefdescription of each will follow.

1. A conventional manual transmission.

2. An automatic transmission.

3. A "racheting" type of continuously or infinitely variabletransmission.

FIG. 1A is a symbolic representation of a four speed manual transmission100 where the different ratio gear sets (first through fourth) 101, 102,103 and 104 are selected manually while the power input from the engine106a is momentarily disconnected by manually operating the clutch 107.The shift linkage (shift lever) 108 is configured so that no two gearsets can be engaged at the same time as this would cause thetransmission to bind up and break.

FIG. 1B is a symbolic representation of an automatic transmission. Inputpower from the engine 106a passes through a torque converter 105 issplit into multiple paths to individual ratio gear sets 108, each ofwhich is composed of an automatically operated clutch hydraulic 109, aratio changing gear set and one side of an over-running clutch or"freewheel 111". The other side of each over-running clutch is connectedto a common output shaft 106b. Ratio change is accomplished by lockingthe clutch of a ratio higher path while unlocking the clutch of thelower ratio path. To avoid excessive shock which would occur if allclutches were unlocked at once allowing the engine to race and thenengaging the higher ratio clutch, the higher ratio clutch is engagedbefore the lower ratio clutch is unlocked. To avoid binding and breakagewhile both clutches are engaged, each ratio gear set drives the commonoutput through an over-running clutch. This allows a higher ratio gearset to drive the common output while over-running the engaged lowerratio gear set.

FIG. 1C is a symbolic representation of a racheting type of continuouslyor infinitely variable transmission. This device uses some rotationaloscillations of variable amplitude from input rotation supplied by theengine 106a. FIG. 1C also shows the index generator 112, the crank arms113, the planetary cage 114 which includes overrunning clutches 116,syncro gears 117, and recombination differential 118 and outputdifferential 119. The desired polarity of these oscillations iscollected by overrunning clutches and delivered to the transmission'soutput 106 shaft to provide an output ratio proportionate to theamplitude of the oscillations generated. These over-running clutcheslock up to transmit the "desired" polarity of oscillations allowing themto drive the output while allowing the "undesired" polarity oscillationsto be over-run and not effect the output. An example of this isdescribed in the Pires patent recited previously.

Over-running clutches, ORCs are needed in a "racheting" style IVT forthe obvious reason that the oscillations generated in this type ofdevice are always characterized by both positive and negative motion.The ORCs are used to collect only the desired polarity and to allow theother polarity to be over-run. These devices do not do this job well forthe following reasons.

1. While ORCs do transmit the proper polarity motion and do allow theother polarity of motion to over-run, without transferring torque theyalso allow for any output motion in excess of the proper polarity input.This accounts for the free-wheeling behavior which prevents anypractical dynamic engine breaking from being developed.

2. Since the ORCs see only polarity of oscillation and not phaserelative to input speed and they reduce the range of the IVT in thatoffsetting the device in one direction has the same effect as offsettingit in the other direction even though the phase is opposite instead ofproducing a reverse output or an augmented forward output effectivelycutting in half the device's adjustment range.

3. ORCs are the weakest link in a transmission and are quite bulky fortheir rated torque as well as being devices of mysterious reliability.Furthermore, they have practical limitations concerning the cycle ratethey can tolerate and the total number of switchings they can survive.

4. It would be desirable to have a transmission that was "locked-up" athigh speed with relatively few moving parts and the IVT can beconfigured this way. However, this automatically loads the ORCs in adirection in line with their over-running direction so that they cannotdeliver torque in this configuration.

5. Finally, ORCs are expensive and require exotic pressurizedlubrication schemes to allow any reliability in operation, as well asrequiring tight tolerances in assembly and expensive bearings to supportall radial and thrust loads.

In view of the foregoing, it is an object of the present invention toprovide a racheting style infinitely or continuously variabletransmission which does not require over-running clutches, therebyeliminating the drawbacks discussed immediately above.

It is a more particular object of the present invention to provide theIVT disclosed herein with an uncomplicated and yet reliable high speedswitching assembly instead of over-running clutches.

As will be described in more detail hereinafter, the transmissiondisclosed herein includes four functional arrangements or meansgenerally. A first means is provided for establishing a rotationalinput. A second means responds to this input for producing a pluralityof different, successive intermediate rotations, each of which varies inspeed and direction (i.e., reciprocates back and forth) in accordancewith its own respective oscillatory waveform such that all of thewaveforms are out of phase with one another in a predetermined way. Athird means is provided and responds to each of the intermediaterotations for producing a plurality of different, successive outputrotations without the aid of any over-running clutches. These outputrotations vary in speed in accordance with their own respectivewaveforms but rotate in only one and the same direction. A fourth meansresponds to the output rotations for ultimately producing a modifiedrotational output.

The IVT designed in accordance with the present invention andparticularly its high speed switching arrangement will be disclosed inmore detail hereinafter in conjunction with the drawings, wherein:

FIG. 1A diagrammatically illustrates a prior art manual transmission;

FIG. 1B diagrammatically illustrates a prior art, standard automatictransmission;

FIG. 1C diagrammatically illustrates an IVT of the prior art typeincluding over-running clutches such as the one disclosed in thepreviously recited Pires patent;

FIG. 1D diagrammatically illustrates an IVT which is designed inaccordance with the present invention to include a specificallyconfigured high speed switching assembly as an alternative toover-running clutches;

FIG. 1 is a front view of an actual working embodiment of the IVTdesigned in accordance with the present invention;

FIG. 2 is a side cutaway view of the IVT of FIG. 1 taken along the axisof an arm crank pair (8a) and (8c), along line 2--2 FIG. 1;

FIG. 3 is a bottom cutaway view taken along the axis of arm crank pair(9b and 9d), taken along line 3--3 in FIG. 1;

FIG. 4 is a rear cutaway view showing the index plate (7) and indexslide (8), taken along the line 4--4 in FIG. 2;

FIG. 5 is a rear cutaway view showing the synchronizing sector gears,taken along line 5--5 in FIG. 2;

FIG. 6 is a rear cutaway view showing the arm planar differentials,taken along line 6--6 in FIG. 2;

FIG. 7 is a front cutaway view showing the commutator gear and reactiongears forming the switching assembly of the IVT, taken generally alongline 7--7 in FIG. 2, and serving as the origin of FIG. 22;

FIG. 8 is a front cutaway view showing the connections of the power pathoriginating with arm cranks (9b) and (9d), taken generally along lines8--8 in FIG. 3 and noting that gears (17a), (17c), (34a), (34c) and (20)have been removed for clarity;

FIG. 9 is a front cutaway view showing the connections of the power pathoriginating with arm cranks (8a) and (8c), taken generally along line9--9 in FIG. 2;

FIG. 10 is a front cutaway view showing the output differential, takengenerally along line 10--10 in FIG. 2;

FIG. 11 is an enlargement of the tooth correction area of FIG. 7;

FIG. 12 is a duplicate view of FIG. 11 with the planetary cage retardedin rotation 22°;

FIG. 13 is a duplicate view of FIG. 11 with the planetary cage retardedin rotation 15°;

FIG. 14 is a duplicate view of FIG. 11 with the planetary cage retardedin rotation 7°;

FIG. 15 is a graphical representation of the rotational speed of armcranks (8a) and (8c), during one input rotation, at 100 rpm input speedclockwise delivered to input shaft (5);

FIG. 16 is a graphical representation of the rotational speed of armcranks (9b) and (9d), during one input rotation, at 100 rpm input speedclockwise delivered to input shaft (5);

FIG. 17 is a graphical representation of the rotational speed of armspiders (13a) and (13c), during one input rotation, at 100 rpm inputspeed clockwise delivered to input shaft (5);

FIG. 18 is a graphical representation of the rotational speed of armspiders (13b) and (13d), during one input rotation, at 100 rpm inputspeed clockwise delivered to input shaft (5);

FIG. 19 is a graphical representation of the rotational speed ofreaction gears (16b) and (16d), during one input rotation, at 100 rpminput speed clockwise delivered to input shaft (5);

FIG. 20 is a graphical representation of the rotational speed ofreaction gears (16b) and (16d), during one input rotation, at 100 rpminput speed clockwise delivered to input shaft (5);

FIG. 21 is a graphical representation of the rotational speed of theoutput spider shaft (25), during one input rotation, at 100 rpm inputspeed clockwise delivered to input shaft (5) and consistent with theindividual component speeds shown in FIGS. 15 through 20;

FIG. 22 is a graphical representation of the rotational speeds of theoutput spider shaft (25), during one input rotation, at 100 rpm inputspeed clockwise delivered to input shaft (5) consistent with variouslateral displacements of the index slide (6); and

FIGS. 23A and 23B diagrammatically illustrate particular features of theswitching assembly shown in FIG. 1D.

Turning to the drawings, attention is now directed to FIG. 1D whichillustrates diagrammatically an IVT device 1 designed in accordance withthe present invention. As seen in this Figure, the invention employs aneccentric member 128 index generator and crank arms to generate variableamplitude rotational oscillations 122 in response to input rotation fromthe engine 106a. Each rotational oscillation is delivered as one inputto a planar differential gear set W, X, Y and Z 123 through syncro gears124 contained in planetary cage 125. Another rotational input to theseplanar differential gear sets is from the commutator gear assembly 126.When the "desired" polarity of oscillation is present at a crank arm,the commutator assembly supplies a supplemental rotational input to thatcrank arm's planar differential gear set. When a planar differential hastwo inputs, it produces an output which is the average of the twoinputs. This intermediate output is then conducted to teh recombinationdifferential 127 where it is combined with any other intermediateoutputs which are allowed by the commutator to produce the output of thetransmission 106b. When the "undesired" polarity of rotationaloscillations is present at a crank arm, the commutator input to thatarm's planar differential gear set is disconnected allowing thatcommutator input "leg" to "freely" rotate which in turn allows theoutput of that "undesired" planar differential to rotate freely and notinhibit the output of the device.

In the device shown in FIG. 1D, the intermediate outputs of the planargear sets W and Y are joined in common to form a pair and theintermediate outputs of the planar gear sets X and Z are joined incommon to form a pair. The two pairs of crank arms associated with thesetwo planar differential pairs are each synchronized so that the arms ina pair always have an equal and opposite rotational oscillation. Thismeans that when one crank arm of a pair has "desired" oscillation, forexample clockwise, the other crank arm has an "undesired" oscillation,for example counterclockwise. Because of the intermediate outputinterconnection of pairs, when one planar differential commutator inputleg is "freely" rotating while its crank arm oscillation is "undesired",its output interconnected with the input of the "desired" set has thedesired output rotation which is composed of the "desired" rotationaloscillation and the engaged commutator supplemental speed. Thisdetermines the speed of the "free" commutator input "leg" of that pairas the average of the "desired" oscillation plus the " desired" setsengaged commutator input plus the "undesired" oscillation. Since thecommutator starts supplying a supplemental input to an arm's planardifferential when that arms oscillation changes from "undesired" to"desired" and since the oscillation of that arm is zero at that point(preparatory to reversing), and since the other arm's oscillation ofthat pair is also zero (due to the synchros), providing only engagedcommutator rotation (due to the common output connection), the speed ofthe "free" commutator input "leg" is the same as the speed of the othercommutator input "leg" (which is connected to the commutator) in thatpair. This means that no shock will occur when the "free" leg of aplanar differential is re-connected to the commutator assembly.

Turning now to FIG. 1, input to the device 3; rotational power (in thiscase clockwise) is supplied by a motor or engine (not shown) connectedto the input shaft-front plate 5' through shaft 5. As seen in FIG. 2,the input shaft-front plate 5' is connected to the planetary rotor 29,support plate 27 and back plate 26 to form a cage which rotates as aunit in response to input rotation supplied to the shaft of plate 5'.This planetary cage is supported for rotation by the front support 2 andthe rear support 4 which are attached to the base 1. The planetary cagecorresponds in function to the planetary assembly 16 disclosed in thepreviously recited Pires patent.

This planetary cage supports for independent rotation four crank arms8a, 9b, 8c and 9d which are arranged radially and equally spaced aboutthe planetary cage axis of rotation. These crank arms are grouped intotwo sets of opposing arms where one set is 90° apart from the other set,corresponding to the shafts 24 in the Pires patent. One set is composedof crank arms 8a and 8c while the other is composed of crank arms 9b and9d. Crank arm pair 8a and 8c and the components associated with it aredetailed in FIG. 2. FIG. 3 is a similar detail pertaining to the 9b and9d set. Each of the four arms has a roller affixed to one end thereofand parallel to the arms axis of rotation but offset from this axis toform a crank. Each of these rollers extend into close fitting slots inthe index plate 7 corresponding to the index plate 84 in the Pirespatent.

Referring to FIG. 4, the slots 60a-d in the index plate 7 are positionedradially about the index plate's axis of rotation, equally spaced, andoriented normal to that axis. The index plate 7 is supported forrotation about its own axis by bearing rollers 62 affixed to the indexslide 6. Index slide 6 is supported by bearing rollers 64 attached tofront support 2 in such a way as to only allow lateral (horizontal)movement. Clearance has been provided by a slot 66 in the index slide 6so that the shaft 5 can pass through and allow lateral motion of indexslide 6 without interference.

Returning to FIG. 1, the lateral motion of the index slide 6 iscontrolled by the adjustment knob 33 by way of screw 31, to which theknob 33 is attached, which freely turns in fixed block 32, but isrestrained by block 32 from lateral movement. In this way, turning theknob 33 turns the screw 31 which forces the index slide 6 by way of thethreaded block 30 attached to it, to move back and forth in response toturning knob 33 clockwise and counterclockwise. This arrangement allowsthe index plate's axis of rotation to be adjusted to any lateralposition from an eccentric position to the left of shaft 5, to aposition concentric to shaft 5, to an eccentric position to the right ofshaft 5 as seen from FIG. 1.

Returning to the crank arms and FIG. 2, it can be seen that crank arms8a and 8c are connected to sector ring hubs 10a and 10c, respectively.Sector hubs 10a and 10c have intermeshing sector gears, FIG. 5, formedin them which force the hubs to have an angular position, relative tothe planetary cage, equal and opposite to each other and therefore theycan only have rotational speed about their own axis equal and oppositeto each other. As shown in FIG. 3, the arm pairs 9b and 9d are similarlysynchronized by sector hubs 11b and 11d but it should be noted that themotion of one arm pair does not effect the other pair.

For the time being, following only the components associated with armcrank pairs 8a and 8c as shown in FIG. 2, note that each sector hub 10aand 10c associated with each crank arm 8a and 8b, respectively supportsfor rotation and drives an internal toothed ring gear 12 meshed with thepinions 14 of a planetary gear set. As seen in FIG. 6, these planetarygear sets are composed of a ring gear 12, a solar gear 15 and pinions 14which are supported for rotation by the fixed pins of the arm spider 13.The solar gear 15 is connected to the reaction gear 16 which is meshedwith the internally toothed commutator gear 28 which is held rigidly bythe bracket 3 fixed to the base as seen in FIG. 7. Note that thecommutator gear has internal teeth over only 180 and is smooth about theremainder of its internal surface. The solar gear 15, in FIG. 6, and thereaction gears 16a 16d, in FIG. 7, are supported for rotation bybearings on the shaft of the arm spider 13 which in turn is supported bybearings in the sector hub, the planetary rotor 29 and the support plate27. Specifically, the shafts of the arm spiders 13a and 13c pass throughthe planetary rotor 29 and drive the gears 17a and 17c, respectively.

Turning now to FIG. 9, gears 17a and 17c mesh with idler gears 34a and34c which are supported for rotation by pins bridging the gap betweenthe planetary rotor 29 and the support plate 27. These idler gears arein turn meshed with the central gear of the output ring gear hub 20which supports for rotation and drives the output ring gear 21 which ismeshed with gear 23 of the compound pinion, as seen in FIG. 2.

Returning to the components associated with the crank arm pairs 9b and9d, and to FIG. 3, note that the path of connections from this arm crankpair is essentially identical except that as shown in FIG. 8, the armspiders 13b and 13d drive gears 18b and 18d, meshed with idler gears 34band 34d which in turn drive the central gear of shaft 19 which drivesthe output sun gear 22 which is meshed with gear 24 of the compoundpinion.

The compound pinion is supported for rotation by, and in turn drives theoutput spider 25 which is supported for rotation by bearings in both theplanetary cage and the rear support 4. A shaft on the output spider 25extends through the rear support 4 to form the output shaft.

As seen in FIG. 11, the tooth correction mechanism 70 can be seen. Thisis composed of a mounting bracket 35 equipped with a stop pin 38 and twopivots upon which are supported for rotation the leading finger 36 andthe trailing finger 37. Both fingers are limited in rotation by the stoppin 38 and are biased towards it by individual spring 39 connected withfinger 37 and a second spring (not shown) connect with finger 36.

Having described the overall device 1D structurally, attention is nowdirected to the way in which it functions. Clockwise rotation from anoutside power source is supplied to the shaft planetary front plate 5'through its shaft which in turn drives the planetary cage and allcomponents carried by it in a clockwise direction. The armcrank pairs8a, 8c, and 9b, 9d drive the index plate 7 in rotation about its ownaxis by way of the crank rollers engaged in the slots 60 of index plate7. The crank arms drive the index plate 7 in synchronized rotation withthe planetary cage because the sector gear hubs 10a, 10c and 11b, 11d,which are intermeshed as pairs and connected to arm cranks 8a, 8c, 9band 9d, respectively, only allow opposing arm cranks to move indirections equal and opposite to each other. For the index plate 7 toadvance or retard in rotation relative the planetary cage, armcrankswould have to rotate in the same direction as their opposing crank ineach set. Furthermore, the center of rotation of the index plate 7 canbe shifted laterally off of the axis of rotation of the planetary cage,by turning knob 33 which rotates screw 31 in a fixed block 32 andthreaded block 30 which forces index slide 6 laterally off center. Inthis eccentric position, the index plate 7 continues to turn insynchrony with the planetary cage but the arm crank pairs are forced tooscillate about their own axes while orbiting with the planetary cage inwhich they are carried, as described in the Pires patent. The frequencyof this oscillation is always one rotational sweep of each arm crankclockwise and counter clockwise, relative to the planetary cage, pereach input rotation. The amplitude of this rotation is a sinusoidalfunction of the ratio of the sine of input angle times lateral offset ofindex slide 6 divided by crank arm length. The equation for crank armspeed is: ##EQU1## Where: ω_(in) is input speed;

L is crank length;

1 is lateral displacement of (6);

θ is planetary cage angular position.

The starting point of each oscillation or its zero point occurs when thearm crank axis is rotationally positioned 90° to the plane defined bythe lateral offset of the index slide 6. The peak amplitude of each armcrank speed always occurs when each crank arm axis is in line with thelateral offset of the index slide 6.

FIG. 15 is a graph of the arm crank 8a and 8c speeds in rpm, during onefull rotation of the planetary cage at 100 rpm. The zero position of thegraph's horizontal axis corresponds to the planetary position shown inFIG. 1. In this example the arm crank length is 1.5" and the index slidelateral offset is 1.30" to the right of the planetary center line asseen in FIG. 1.

FIG. 16 is a graph of arm crank 9b and 9d speeds in rpm, during one fullrotation of the planetary cage at -100 rpm. The zero position of thegraph's horizontal axis corresponds to the planetary position shown inFIG. 1. In this example, the arm crank length is 1.5" and the indexslide lateral offset is 1.30" to the right of the planetary center lineas seen in FIG. 1.

Following the path of these oscillations from the arm cranks 8a and 8cin FIG. 2, it can be seen that these rotational oscillations aredelivered to the planar gear sets by way of the ring gears 12. The otherinputs to the planar gear sets are the sun gears 15a and 15c driven bythe reaction gears 16a and 16c running in the stationary commutator gear28. Looking at FIG. 7, it can be seen that the reaction gears 16a and16c are only driven by the commutator during one half of an inputrotation due to the 180° of internal teeth in commutator 28 and are freeduring the other half of an input rotation. It should also be noted thatwhen one reaction gear 16 is driven for example, gear 16c, its opposingreaction gear, for example, gear 16a is free. This is also true for theother set of reaction gears 16b and 16d, so one reaction gear of eachpair is always driven while the other reaction gear of each pair isfree. The timing of this change over from free to driven occurs wheneach reaction gear is in a position 90° from the horizontal planedefined by the lateral motion of the index slide 6. This is the precisetime in the input rotation when the arm crank associated with thatreaction gear is at rest relative to the planetary cage. At that moment,the ring gear oscillations to the planar gear sets are the same speedsince the oscillations present at arm cranks 8a and 8c have stoppedpreparatory to reversing. And, the speed of the arm spiders 13a and 13care the same since they drive, in tandem, the central gear 20 throughidler gears 34a and 34c. Therefore, the sun gear 15a and 15c speeds mustbe the same. This means that any "free" reaction gear will automaticallyassume the proper rotational speed for running in the fixed commutatorgear 28 at the time it enters the toothed half of the commutator gear28. So, the speed of both arm spider gear sets 13a and 13c is theaverage of the engaged reaction gear speed plus the speed of oscillationof the arm crank associated with the engaged reaction gear, adjusted bythe ratio of the ring gear 12 gear pitch diameter to the solar gear 15gear pitch diameter. The exact equations for the arm spider speed is:##EQU2## Where: R_(com) is the pitch diameter of commutator gear (28);

R_(react) is the pitch diameter of the reaction gear (16);

ω_(re) is the speed of a reaction gear (16) when engaged in thecommutator gear (28).

and ##EQU3## Where: ω_(spider) is the rotational speed of (13);

R_(ring) is the pitch diameter of (12);

R_(sun) is the pitch diameter of (15).

FIG. 17 is a graph of the speed of the arm spider pair 13a, 13c in rpmusing the arm crank speeds and the same 100 rpm input speed specified inFIG. 15.

FIG. 18 is a graph of the speed of the arm spider pair 13b, 13d in rpmusing the arm crank speeds and the same 100 rpm input speed specified inFIG. 16.

Once the arm spider speeds are known, computing that speed of the freereaction gear for each arm spider set is as follows using the aboveterms and ω_(react) to represent the free reaction gear speed: ##EQU4##

FIG. 19 is a graph of the reaction gear 16a and 16c speeds for theconditions found in FIGS. 15 and 17. Note by comparison to FIG. 7 thatthe "free" reaction gears assume the speed of the engaged reaction gearsat the same time they re-enter the commutator gear 28.

FIG. 20 is a graph of the reaction gear 16b and 16d speeds for theconditions found in FIGS. 16 and 18. Note by comparison to FIG. 7 thatthe "free" reaction gears assume the speed of the engaged reaction gearsat the time they re-enter the commutator gear 28.

In one embodiment the interface between the reaction "gears" 16a 16d andthe commutator "gear" 28 could be a traction element where the reactiongears are replaced by rollers and the commutator is replaced by aninterrupted track and no further effort would be necessary to assure"meshing". However, in the preferred embodiment, where a gearedinterface is employed, a tooth correction mechanism is required toassure that the "free" reaction gear meshes properly with the commutatorgear 28 upon re-entry into the toothed portion of the commutator gear.This is required since the "free" reaction gear has advanced or retarded(rotated about its own axis) an unpredictable amount in response to theoscillation of the armcrank associated with the opposing "driven"reaction gear. To compensate for this the reaction gear must be advancedor retarded at most 1/2 of a gear tooth spacing upon re-entry, as willbe described below.

FIG. 11 is an enlargement of sections of commutator gear 28,illustrating particularly tooth correction mechanism 70. FIG. 12 showsreaction gear 16C just prior to encountering the tooth correction device70 which is in the extended position. In this position, both the leadingfinger 36 and the trailing finger 37 are fully extended by the biassprings 39 and 40. In this position the tips of the two fingers arespaced apart slightly less than the gap between the two reaction gearteeth. Because of this spacing, one or the other or both of the fingersmust fall in a tooth spacing of the on-coming reaction gear 16C. As thereaction gear 16C progresses towards engagement with the internal teethof the commutator gear 28, both fingers are forced downward againsttheir springs which spreads the gap between the two fingers. This actioncauses the finger closest to engagement to move into a reaction geartooth gap to control the gears rotational position. At the same time thefinger furthest from engagement is caused to advance or retard to thenext tooth gap as seen in FIG. 13. After this occurs, the reaction gearmoves to a position between the axis of the planetary rotation and thepoint between the two finger tips. At this position both fingers areforced down until the rocker stop 42 on the rear portion of the trailingfinger interferes with the back surface of the leading finger to limitboth fingers downward travel, FIG. 14. In this position both fingersoccupy positions along the pitch diameter of the gear 28 and are inpositions identical to where commutator gear teeth would be if extendedthat far. As such, they have adjusted the position of the reaction gearteeth so that it will progress onward into mesh with the commutatorgear. This does not bind the overall device even though this toothcorrection mechanism is acting upon the free reaction gear 16C while itsopposing reaction gear 16A is still being driven by the commutator gear,since even a precision gear train has enough cumulative backlash toallow this. It does provide for control of at least one reaction gearset of each arm crank pair even at the reaction gears change-over pointfrom driven to free.

To summarize, the armcranks and index assembly produce oscillations atthe arm cranks when the index center of rotation is displaced laterally(off-center) from a position concentric with the axis of rotation of theplanetary cage. These oscillations are one of two inputs to the armplanar gear sets (planar differentials), the other input being rotationfrom the reaction gear 16A, 16B, 16C or 16D but only when the reactiongear is engaged with the commutator gear 28. This means that theoscillation of an arm crank can only contribute to the speed of an armspider 13 if its associated reaction gear is engaged with the commutatorgear. If the reaction gear of an arm crank st is "free" from thecommutator, it rotated in response to its associated arm crankoscillation, allowing the common arm spiders 13 in that pair to rotatein response to the engaged reaction gear and at the speed of theoscillation present at the arm crank associated with the engagedreaction gear.

This rotational speed seen at the arm spiders plus the orbital speed ofthe planetary cage is conducted to the central gear of the output ringhub 20 by way of gears 17a, 17c, 34a and 34c. This hub supports anddrives the ring gear 21 of the output differential.

The function of arm cranks 9b and 9d and their connections are identicalto that of arm cranks 8a and 8c described above except that the armscranks 9b and 9d are mounted in the planetary cage positionally 90° fromarm pair 8a and 8c and the arm spiders associated with them, 13b and13d, are connected to the central gear of shaft 19 by way of gears 18band 18d and idler gears 34b and 34d. As with the arm spiders 13a and13c, when the geared connections from 13b and 13d feed inward to thecentral gear of 19, a planetary rotation speed is also delivered to thegear of 19 which in turn drives the output differential solar gear 22.

The rotational speed of the two arm spider pairs plus input rotationbecome the two inputs to the output planar differential. The equationfor the output spider-shaft speed 25 is as follows: ##EQU5## Where:R_(ring) is size of (21);

R_(sun) is size of (22);

R_(sPin) is size of (24);

R_(rPin) is size of (23);

ω_(out) is speed at (25).

FIG. 21 is a graph of the output speed at shaft 25 for the conditions inthe previous FIGS. 15-20.

FIG. 22 is a graph of the output speeds at shaft 25 in response todifferent lateral displacements of the index slide 6.

It can be seen from FIG. 22 that the above described mechanism iscapable of producing average output to input speed from +11.72 rpm(reverse) counterclockwise to zero rpm (neutral) to full speed -83.72rpm (forward) clockwise. This device is different from the prior art inthat the output ratio is controlled when the device is driving an outputload as well as when it is being driven by the output load (retarding).This is not true for devices which contain over-running clutches asthese devices "free wheel" when they should be retarding.

To further summarize the present invention, reference is again made toFIG. 1D in conjunction with FIG. 23A and 23B. At the beginning of thedetailed description of the present invention, before device 3 wasdescribed in detail in conjunction with FIGS. 1-22, it was describedgenerally in conjunction with a symbolic illustration in FIG. 1D. Havingnow provided a detailed description of the device, it is believedworthwhile to again discuss or summarize the operation of device 3 inconjunction with the symbolic illustration in FIG. 1D and thesymbolically illustrated aspects of the device shown in FIGS. 23A and23B.

The INDEX GENERATOR illustrated in FIG. 1D symbolically depicts the"front end" of the device including crank arms 8A, 8B, 9A and 9B and therotational oscillations they produce, which are designated at A, B, Cand D. These oscillations respectively serve as inputs to the planargear sets or differentials which in FIG. 1D are designated at W, X, Yand Z. Note that the rotational oscillation A serves as an input to thedifferential W, rotational oscillation B serves as an input to thedifferential X, rotational oscillation C serves as an input to thedifferential Y and rotational oscillation D serves as an input to thedifferential Z. It should further be recalled that the rotationaloscillations A and C are 180° out of phase with one another, therotational oscillations B and D are 180° out of phase with one anotherand the two sets A/C and B/D are 90° out of phase. It should also benoted here that the rotational oscillations provided by these crank armsets are input to differentials W, X, Y and Z and are provided in theprecise manner disclosed in the previously recited Pires patent, asstated above.

Still referring to FIG. 1D, the commutator gear (shown in FIG. 7) isconnected to each of the planar differentials W, X, Y and Z as secondinputs. In actuality, the four reaction gears 16A, 16B, 16C and 16Dforming part of the commutator serve as second inputs to the fourdifferentials. At the same time, each of these planar differentials hasits own output which serves as one of two inputs to the combinationdifferential. In this regard, note that the outputs of the planardifferentials W and Y are connected together to serve as one input tothe recombination differential and the outputs from planar differentialsX and Z are connected together and serve as the other input to therecombination differential. Since the outputs at these planardifferentials are produced and directed into the recombinationdifferential, the latter functions to produce an output in the mannerdescribed above and also in the manner described in the previouslyrecited Pires patent.

Attention is now directed to an operational description of the device 1Das symbolically illustrated in FIGS. 1D and in FIGS. 23A and 23B. At theoutset, let it be assumed that the device is to operate on the positivepolarities of the rotational oscillations. Thus, ultimately one input tothe recombination differential will receive successive positivehalf-cycles from the rotational oscillations A and C while the otherinput will receive successive positive half cycles from the rotationaloscillations B and D, keeping in mind that these latter two positivehalf cycles are 90° out of phase with the former positive half cycles.It should also be kept in mind that when a positive half cycle ofrotational oscillation A is applied to its planar differential W, thecorresponding negative half cycle of rotational oscillation C is beingapplied to its planar differential Y. This is also true for therotational oscillations B and D.

With the foregoing in mind, attention is now directed to FIGS. 23A and23B which illustrate how the two planar differentials W and Y producetheir successive positive half cycles as a result of rotationaloscillations A and C. Let it be assumed first that the darkened positivehalf cycle of rotational oscillation A is being applied to its input ofthe planar differential W. During that same time span, the correspondingreaction gear 16A serving as a second input to the planar differential Wis connected to the commutator 28 (as opposed to being free) and therebyprovides its own input to planar differential W, as indicatedsymbolically at 82 in FIG. 23A. As a result of these two inputs, thecorresponding rotational half cycle is provided at the output of theplanar differential for inputting to the recombination differential.During the next half cycle of rotational oscillation A, that is, duringthe darkened negative half cycle illustrated in FIG. 23B, the reactiongear 16A is disconnected from the commutator, as diagrammaticallyindicated at 82. Thus, during the time span that the negative half cycleof rotational oscillation A is present, there is no second input to theplanar differential W. As a result, the planar differential W duringthat time span does not produce its output. However, as illustrated inFIG. 23B, the output from the planar differential Y is connected to theoutput of planar differential W as stated previously. Moreover, asstated previously, during the very time span that the negative halfcycle of signal A is being applied to the differential W, the darkenedpositive half cycle of the rotational oscillation C is being applied toits input of differential Y. In addition, the reaction gear 16C whichserves as a second input to the differential Y is being driven by thecommutator gear 28 and, hence, serves as a second input to thedifferential Y. As a result, the output to the differential Y producesits own positive rotation. These successive outputs from the planardifferentials W and Y are indicated at 86 and 88, respectively. Thus,one input to the recombination differential receives successive positiverotations 86 and 88. In the same way, the two planar differentials X andZ produce corresponding positive rotations to the other input of therecombination differential, although these latter rotations are 90° outof phase with the rotations 86 and 88, as indicated previously.

It should be noted that the positive rotations 86 and 88 resulting fromrotational oscillations A and C and their counterparts resulting fromthe rotational oscillations B and D are provided without utilizingover-running clutches, as is the case in the previously recited Pirespatent. This is because of the way in which the commutator is designedand synchronized with the rotational oscillations. Specifically, duringthe presence of the positive half cycle of the rotational oscillation A,the reaction gear 16A is in its drive mode and during the negative halfcycle of rotational oscillation A, reaction gear 16A is in its freemode. This is also true for each of the other rotational oscillationsand their respective reaction gear, all of which are 90° apart from oneanother, as illustrated in FIG. 7.

What is claimed is:
 1. A commutator assembly for use in a transmissionsuch as an oscillating ratchet style continuously or infinitely variabletransmission, said assembly comprising:(a) a stationary commutatormember having a continuous surface, one segment of which defines acontinuous drive surface and a second segment of which defines anon-driving surface; (b) a plurality of reaction members mounted forrotation about their own axes adjacent said commutator member and spacedapart about the center of the latter at predetermined distances from oneanother; and (c) means supporting all of said reaction members forrotation about the center of said commutator member such that eachreaction member engages the drive surface of said commutator member andis caused to rotate about its own axis as it passes over the drivesurface for producing its own reaction rotation and is allowed tofree-wheel about its own axis as it passes over the non-driving surfaceof said commutator member whereby it produces no reaction rotation.
 2. Acommutator assembly according to claim 1 wherein:(a) said sectionmembers are gears including external drive teeth; (b) the drive surfaceof said commutator member includes cooperating drive teeth positioned toengage the drive teeth of said reaction gears; and (c) said non-drivingsurface is spaced from and does not engage the drive teeth of saidreaction gears.
 3. A commutator assembly according to claim 2 whereinsaid commutator member includes means for insuring that the teeth ofeach of said reaction gears properly engages the drive teeth of thecommutator member's drive surface, as each reaction gear approaches thedrive surface from the commutator member's non-driving surface.
 4. Acommutator assembly according to claim 1 wherein the continuous surfaceof said commutator member is annular.
 5. A commutator assembly accordingto claim 4 wherein said annular surface faces inward.
 6. A commutatorassembly for use in a transmission such as an oscillating ratchet stylecontinuously or infinitely variable transmission, said assemblycomprising:(a) a stationary commutator member having a radially inwardfacing annular surface, one-half of which defines a continuous drivesurface and the other half of which defines a non-driving surface; (b)first, second, third and fourth reaction members mounted for rotationabout their own axes within said commutator member and positioned aboutthe center of the latter 90° from one another such that the first andthird reaction members are 180° apart and the second fourth reactionmembers are 180° apart, and (c) means supporting all four of saidreaction members for rotation about the center of said commutator membersuch that each reaction member engages the drive surface of saidcommutator member and is caused to rotate about its own axis as itpasses over the drive surface for producing its own reaction rotationand is allowed to free-wheel about its own axis as it passes over thenon-driving surface of said commutator member whereby it produces noreaction rotation.
 7. A commutation assembly according to claim 6wherein:(a) said reaction members are gears including external driveteeth; the drive surface of said commutator member includes cooperatingdrive teeth positioned to engage the drive teeth of said reaction gears;and (b) said non-driving surface is spaced from and does not engage thedrive teeth of said reaction gears.
 8. A commutator assembly accordingto claim 7 wherein said commutator member includes means for insuringthat the teeth of each of said reaction gears properly engages the driveteeth of the commutator member's drive surface, as each reaction gearapproaches the drive surface from the commutator member's non-drivingsurface.
 9. An apparatus for modifying an input rotation to produce amodified rotational output, comprising:(a) first means including a firstmember for imparting to said first member said input rotation; (b)second means including a second member for imparting to said secondmember solely from said input rotation a first epicyclic motionconsisting of an orbital component rotation in the same direction and atthe same speed as said input rotation and a rotational component; (c)third means including a further second member for imparting to saidfurther second member solely from said input rotation a second epicyclicmotion consisting of an orbital component and a rotational component,said second epicyclic motion being identical to said first epicyclicmotion, except that the rotational component of said second epicyclicmotion is out of phase with the rotational component of said firstepicyclic motion; and (d) fourth means operatively connected with saidsecond and third means and including a plurality of third members whichrotate uni-directionally in response to the rotational components ofmotion of said second members, without the aid of over-running clutches,said third members uni-directionally rotating in accordance with theirown respective speed waveforms, said fourth means including (i) aplurality of differential gear arrangements, one for each of said secondmembers, each differential gear arrangement including first and secondinputs and an associated one of said third members which serves as anoutput, the first input of each differential gear arrangement beingcoupled with an associated one of said second members for receiving thatmember's rotational component, and each arrangement's output generatingits own one of said unidirectional rotations in response to a receivedrotation at its first input simultaneously with a reaction rotation atits second input, each of said outputs being coupled to fifth means, and(ii) a commutator assembly including means for producing a reactionrotation for each of said differential gear arrangements, each of saidreaction rotations being coupled to the second input of an associatedone of said differential gear arrangements, whereby the combination ofrotations of the first and second inputs to any given differential geararrangements results in an associated one of said unidirectionalrotations at the output of that arrangement, without the aid of anover-running clutch; and (e) said fifth means operatively connected withsaid fourth means and including a fourth output member which rotates inresponse to the collective rotations of said third members and whichdoes so in a modified way relatively to said rotational input, wherebyto provide a modified rotational output.